Maintaining exercise participation among patients who have completed cardiac rehabilitation is integral to secondary prevention of coronary events and cardiac re-hospitalization. Patients in Phase II cardiac rehabilitation programs, a majority being older adults, participate in regular supervised exercise during the program; however, long-term adherence to exercise is poor, with only 30% reporting regular exercise at 12 month follow-ups. To promote exercise maintenance after completion of a 12 week Phase II rehabilitation program, we propose to offer a theoretically-based intervention that we have used successfully to promote exercise among older, primary-care patients. This program (Maintenance Counseling) includes brief advice from the Cardiac Rehabilitation case manager at Phase II program discharge followed by telephone counseling based on the Transtheoretical Model of Behavior Change and Social Cognitive Theory. Health educators will provide the telephone-based intervention over 6 months. Using a randomized controlled design, 180 patients will be assigned to Maintenance Counseling or Brief Advice plus Contact Control. Outcome assessments will include an exercise tolerance test (baseline/post-rehabilitation and 6 months), self reported exercise participation, motivational readiness for exercise, and objective activity monitoring at baseline, 6, 12 and 18 months. These data will help to identify whether telephone-based exercise counseling is an effective strategy for sustaining regular exercise and fitness among cardiac rehabilitation patients thereby contributing to secondary prevention of coronary heart disease. [unreadable] [unreadable]